For the purpose of higher production efficiency of a linear type bottle filling device used to fill milk and milk beverages, bottles are normally arranged in a line, where filling, capping and cap tightening are conducted simultaneously. In this case, plastic caps after arrangement are required to be secondarily distributed to their corresponding slideways in an even manner After being sterilized, the plastic caps are precisely put on bottle openings subject to the predetermined requirements in order to facilitate the following tightening process. Conventionally, bottle caps are branched in the manner that the number of passageways increases geometrically, in other words, one passageway branches into two passageways, two into four, four into eight and the like. The capping is achieved by a power-free cap grabbing, more specifically, the bottle caps sliding off the preset slideways are blocked by two leaf springs at the front end of a grabbing head when the bottle caps are in an inclined state. As the front edge of a bottle cap is lower than the level of the bottle opening while the rear edge is higher than said level. When the bottles horizontally pass through the cap grabbing head, the bottle openings grab the front edges of the bottle caps, which are then carried away and fall on the bottle openings, during which the leaf springs block the following cap.
The aforesaid solution has the disadvantages that: 1. As the cap passageways increase geometrically, this will bring about huge-sized passageways in case of a great number of bottles are in the line; 2. The bottle caps are not blocked when passing through a sterilizing chamber, therefore the bottle caps are arranged all over the cap slideways. It is no problem for sterilization during normal working process but unfavorable for the beginning. When the bottle caps pass though the cap slideways rapidly due to less bottle caps distributed therein, consequently, the sterilizing is incomplete, the hygienic quality of the final products will be affected; 3. When grabbing is used for capping, if the bottle caps fail to precisely fit with the bottle openings, the bottle caps would not be covered properly. It will affect the following tightening effects. Furthermore, the grabbing head is disposed with the leaf springs for plastic caps, it is sometimes unreliable that the following cap may be carried over together with the previous one.